General guidance on supplementation

Vitamin C: supplementation should provide the RNI 75mg/day in adults, (additional 35mg/day may be considered for smokers). Note: tissue saturation occurs at 200mg/day

Iron: supplementation should provide the RNI 8.7mg/day in men (and women over 50); 14.8mg/day in women (under 50). Regular monitoring of iron profile should be undertaken and supplementation discontinued when stores are returned to normal levels. Note: excess iron intake can cause a metallic taste, affecting appetite

Zinc: supplementation should provide the RNI 9.5mg/day in men; 7mg/day in women. Note: doses >40mg/day can cause toxicity. Excess zinc reduces the absorption of other vitamins and minerals, which can reduce the immune response